.htabmain{
    /*text-align: center;*/ /*让div内部文字居中*/
    background-color: #fff;
    /*
    border-radius: 20px;
    width: 300px;
    height: 350px;
    */
    margin: auto;
    position: absolute;
    left: 0;
    right: 0;
    /*
    top: 0;
    bottom: 0;
    */
}
